Casting door-knobs upon their collars



, To all whom t may concern.'

WILLIAM HIGGS, OF UTICA, NEW YORK.

CASTING -DOOR-KNOBS 'UPON THEIR COLLARS.

Specification of Letters Patent No.r 4,884, dated December 10, 1846.

Be it known that I, WILLIAM HIGGs, of thej' city of Utica, in the State of New York, have invented a new and Improved Mode offl Casting Door-Knobs; and I do hereby declare that the following is a full and eXact description.

The nature of my invention consists in contriving the means of casting said knobs whole and yet hollow, avoiding the necessity of brazing the two halves together, after being cast separate; or of closing an opening in the head, orfront of the knob after cast, as has heretofore been done.

To enable others skilled in the art, to make and use my invention, I will proceed to describe its construction, and the manner of molding and casting the same; reference being had to the drawings hereto annexed, making a part of this specification. l

Figure 1 of the4 said drawings is a core around which to cast the knob. The light colored part A B is made of sand, in the usual mode of making sand cores, and is of a size, and shape corresponding to the cavity intended in the interior of the knob. C is a cylindrical tube of sheet iron, and is inserted in the sand core when the latter is made, and before it is dry, so that when the core is dried, the tube is firmly fixed in it. This tube serves to give vent to the gases and vapor issuing from the core when the melted metal is cast around it, and at the same time to hold the core in its proper position.

Fig. 2 is the neck of the knob and is first cast separately. It is cast hollow by the use of a cylindrical sand core, the pattern for the same being in two parts in the ordinary way, the hollow through the center being just large enough to slip over the tube C, Fig. 1, and to screw on the spindle in the usual way when put in use. Its outward form may be of any figure as heretofore made, but its upper end is cast in a dovetailed shape as seen at D D Fig. 2 with aV notch in opposite sides as seen at e, to hold the. knob firmly when cast around it. When the knob is cast around it, the tube C is inserted in this brazen neck, as seen in Fig. 3, and the metal cast around the sand core fillsthe space seen between it and the dotted line. The process of molding and of casting the metal around this sand core and this dovetailed neck is as follows: Fig. 5 represents the first pattern used in this process. It consists of the neck of the knob already cast (Fig. 2) with, the upper, or dovetailed. end, insertedin a cavity suited to 1t, in the upper side of the half pattern of wood, or metal, E E Fig. 5. The other half of this Wood pattern, being seen in Fig. 7. The whole wood pattern, when put together being the form intended for the knob, and

bisected for the convenience of molding, inl

the usual way through the center. This compound pattern Fig. 5, is set upright, as seen in the figure, on a plain molding board, and the molders ask being placed around it, the sand is embedded around it in the usual way. The flask and contents are then turned over, and being laid upon the molding board with the reverse side upward, a section of the woodenv pattern E E is seen making an even plane with the surface of the sand, as shown in Fig. 6; the brass neck connected with it, being out of sight in the sand beneath. The other half of the knob pattern Fig. 7, with its plane side down, is then laid upon its fellow, Fig. 6, the pins or dowels seen in its surface being inserted in corresponding holes seen in the surface ofy Fig. 6. The whole forming the perfect shape of the intended knob. Parting sand is then dusted over the whole surface, and the other half of the flask being laid down surrounding it, the sand is again rammed around the pattern in the usual way. The upper part of the flask, with the sand contained in it is then lifted, and the two halves, one after the other of the wooden lmob pattern are taken out, leaving the brass neck still in the sand below. The core and tube Fig. 1, are then set in the cavity thus made, the tube C standing in the hollow of the brass neck below, and the sand core sustained by it, is held within the elliptical space in such a position as to allow the metal to pass around it, and to fasten to its dovetailed neck. 4For it is plain that when the other half of the flask is replaced ready for casting, the cavity to be filled by the melted metal, is a space corresponding to that seen between the sand core and the as before stated, the tube C Figs. 1 and .3,

For,

10 'to secure by Letters Patent is,

sand core and tube connected as above def scribed, and shown Vin Fig. l, and the placing Vof these in conjunction for`the`reception of vthe metal in casting the knob as shown in Fig. 3, the Whole being molded arranged and performed substantially in the manner above set forth and described.

y2. I also claim the combination of the metal tube C `Witlithe sand'core A B Fig. 1, and the dovetailing of the neck D D Fig. 2, in the manner and for the purpose set `forth. AVILLAM HIGGS. Witnesses.:

WILLIAM BAKER,

C. JOHNSON. 

